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Search Publications by: Alexander Kramida (Fed)

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Displaying 26 - 50 of 79

Ionization potentials of superheavy elements No, Lr, and Rf and their ions

October 3, 2016
Author(s)
Vladimir A. Dzuba, M.S. Safronova, Ulyana I. Safronova, Alexander Kramida
We predict ionization potentials of superheavy elements No, Lr, and Rf and their ions using a relativistic hybrid method that combines con figuration interaction (CI) with the linearized coupled-cluster approach. Extensive study of the completeness of the

NIST program of spectroscopic data for light elements of fusion interest

January 15, 2015
Author(s)
Joseph Reader, Alexander Kramida, Yuri Ralchenko, Wolfgang L. Wiese, Jeffrey R. Fuhr
This paper summarizes work at the National Institute of Standards and Technology (NIST) in support of the IAEA Coordinated Research Project on “Light Element Atom, Molecule and Radical Behaviour in the Divertor and Edge Plasma Regions.” It includes

Extended and Revised Analysis of Singly Ionized Tin: Sn II

October 28, 2014
Author(s)
K. Haris, Alexander Kramida, A. Tauheed
The electronic structure of singly ionized tin (Sn II) is partly a one-electron and partly a three-electron system with ground configuration 5s25p. The excited configurations are of the type 5s2nℓ in the one-electron part, and 5s5p2, 5p3 and 5s5pnℓ (nℓ =

Energy Levels And Spectral Lines Of Quadruply Ionized Iron (Fe V)

April 24, 2014
Author(s)
Alexander Kramida
This compilation revises and extends the previously recommended list of energy levels of quadruply ionized iron (Fe V) and provides a comprehensive list of observed spectral lines and transition probabilities in this spectrum. The new level optimization

Using and creating databases for data analysis in laser spectroscopy

January 1, 2014
Author(s)
Alexander Kramida
A brief review of existing atomic spectroscopy databases is given with an emphasis on databases relevant to laser spectroscopy research. Key data elements in these databases are described. A strategy of building a specialized relational database for laser

Energy levels and spectral lines of singly ionized manganese (Mn II)

March 7, 2013
Author(s)
Alexander Kramida, Jean E. Sansonetti
This compilation revises the previously recommended list of energy levels of singly ionized manganese (Mn II) and provides a comprehensive list of observed spectral lines and transition probabilities in this spectrum. The new level optimization takes into

Extension and new level optimization of the Ne IV spectrum

January 13, 2012
Author(s)
Alexander Kramida, C M. Brown, Uri Feldman, Joseph Reader
Spectra of Ne emitted by a Penning discharge were recorded in the extreme ultraviolet (EUV) region between 140 Å and 359 Å on a 10.7 m grazing-incidence spectrograph with phosphor storage image plates. These spectra provided 33 newly identified lines of Ne

Recent progress in spectroscopy of tungsten

May 20, 2011
Author(s)
Alexander Kramida
This contribution reviews experimental and theoretical work on spectroscopy of tungsten published since the last critical compilation of the energy levels and spectral lines of highly ionized tungsten [K09]. Since then, 15 new experimental studies were

Recent developments in the NIST Atomic Databases

May 11, 2011
Author(s)
Alexander Kramida
New versions of the NIST Atomic Spectra Database (ASD, v. 4.0) and three bibliographic databases (Atomic Energy Levels and Spectra, v. 2.0, Atomic Transition Probabilities, v. 9.0, and Atomic Line Broadening and Shapes, v. 3.0) have recently been released

Re-optimized energy levels and Ritz wavelengths of 198Hg I

May 10, 2011
Author(s)
Alexander Kramida
Energy levels and observed spectral lines of 198Hg I were recently compiled at the National Institute of Standards and Technology (NIST) [E. B. Saloman, J. Phys. Chem. Ref. Data 35, 1519 (2006)]. In that compilation, the energy level values were optimized

The program LOPT for least-squares optimization of energy levels

February 1, 2011
Author(s)
Alexander Kramida
The article describes a program that solves the least-squares optimization problem for finding the energy levels of a quantum-mechanical system based on a set of measured energy separations or wavelengths of transitions between those energy levels, as well

Atomic Spectroscopic Databases at NIST

October 28, 2010
Author(s)
Joseph Reader, Alexander Kramida, Yuri Ralchenko
We present recent work at NIST to develop and maintain databases for spectra, transition probabilities, and energy levels of atoms that are astrophysically important. We also describe our programs to critically compile these data as well as the recently

Revised interpretation of the Na I EUV absorption spectrum

September 27, 2010
Author(s)
Alexander Kramida
Spectral data for neutral sodium were recently compiled by Sansonetti (2008 J. Phys. Chem. Ref. Data 37 1659). In that compilation, some of the energy levels of the 2p53snl configurations were quoted from the studies of the absorption spectrum in the

Extension of the resonance line series of Mg III

December 1, 2009
Author(s)
C M. Brown, Alexander Kramida, Uri Feldman, Joseph Reader
Spectra of Mg emitted by a Penning discharge were recorded in the extreme ultraviolet (EUV) on a 10.7-m grazing-incidence spectrograph with phosphor image plates. The spectra provided nine new lines of Mg III between 156 and 166 Å and allowed us to improve

A Critical Compilation of Energy Levels and Spectral Lines of Neutral Boron

October 16, 2008
Author(s)
Alexander Kramida, A N. Ryabtsev
Observed spectral lines of neutral boron are critically compiled. Fromselected best measurements, an improved and extended set of energy levels isderived for the two most abundant isotopes, 11B and 10B. The ionization energyis determined to a greater

The Ne II Spectrum

October 16, 2008
Author(s)
Alexander Kramida, Gillian Nave
Spectra of neon-filled hollow cathode discharge lamps were observed by means of high-resolution Fourier-transform spectroscopy (FTS) covering the region from vacuum ultraviolet to near infrared. By combining these new measurements with results of other FTS

Extended EUV and UV Spectrum of Ne II

July 1, 2006
Author(s)
Alexander Kramida, C M. Brown, Uri Feldman, Joseph Reader
The extreme ultraviolet (EUV) spectrum of Ne emitted by a Penning discharge has been recorded at high resolution with a 10.7 m grazing incidence spectrometer. Based on the recorded spectra 75 new Ne II lines have been observed between 286 and 325